X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=libringbuffer%2Ffrontend_api.h;h=6a06bba2c2393ba139bc506a8f88bb4027b59ea9;hb=refs%2Fheads%2Fstable-2.0;hp=75146e60bef33a23937f71d27e254b486ae1f7c9;hpb=9f3fdbc68877e1f12b6cedb15ef76d9af9b48bac;p=lttng-ust.git diff --git a/libringbuffer/frontend_api.h b/libringbuffer/frontend_api.h index 75146e60..6a06bba2 100644 --- a/libringbuffer/frontend_api.h +++ b/libringbuffer/frontend_api.h @@ -1,24 +1,36 @@ -#ifndef _LINUX_RING_BUFFER_FRONTEND_API_H -#define _LINUX_RING_BUFFER_FRONTEND_API_H +#ifndef _LTTNG_RING_BUFFER_FRONTEND_API_H +#define _LTTNG_RING_BUFFER_FRONTEND_API_H /* - * linux/ringbuffer/frontend_api.h + * libringbuffer/frontend_api.h * - * (C) Copyright 2005-2010 - Mathieu Desnoyers + * Copyright (C) 2005-2012 Mathieu Desnoyers + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; only + * version 2.1 of the License. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA * * Ring Buffer Library Synchronization Header (buffer write API). * * Author: - * Mathieu Desnoyers - * - * See ring_buffer_frontend.c for more information on wait-free algorithms. - * See linux/ringbuffer/frontend.h for channel allocation and read-side API. + * Mathieu Desnoyers * - * Dual LGPL v2.1/GPL v2 license. + * See ring_buffer_frontend.c for more information on wait-free + * algorithms. + * See frontend.h for channel allocation and read-side API. */ #include "frontend.h" -#include "ust/core.h" #include #include @@ -37,16 +49,16 @@ * section. */ static inline -int lib_ring_buffer_get_cpu(const struct lib_ring_buffer_config *config) +int lib_ring_buffer_get_cpu(const struct lttng_ust_lib_ring_buffer_config *config) { int cpu, nesting; rcu_read_lock(); - cpu = ust_get_cpu(); + cpu = lttng_ust_get_cpu(); nesting = ++lib_ring_buffer_nesting; /* TLS */ cmm_barrier(); - if (unlikely(nesting > 4)) { + if (caa_unlikely(nesting > 4)) { WARN_ON_ONCE(1); lib_ring_buffer_nesting--; /* TLS */ rcu_read_unlock(); @@ -59,7 +71,7 @@ int lib_ring_buffer_get_cpu(const struct lib_ring_buffer_config *config) * lib_ring_buffer_put_cpu - Follows ring buffer reserve/commit. */ static inline -void lib_ring_buffer_put_cpu(const struct lib_ring_buffer_config *config) +void lib_ring_buffer_put_cpu(const struct lttng_ust_lib_ring_buffer_config *config) { cmm_barrier(); lib_ring_buffer_nesting--; /* TLS */ @@ -73,13 +85,13 @@ void lib_ring_buffer_put_cpu(const struct lib_ring_buffer_config *config) * returns 0 if reserve ok, or 1 if the slow path must be taken. */ static inline -int lib_ring_buffer_try_reserve(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer_ctx *ctx, +int lib_ring_buffer_try_reserve(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer_ctx *ctx, unsigned long *o_begin, unsigned long *o_end, unsigned long *o_old, size_t *before_hdr_pad) { struct channel *chan = ctx->chan; - struct lib_ring_buffer *buf = ctx->buf; + struct lttng_ust_lib_ring_buffer *buf = ctx->buf; *o_begin = v_read(config, &buf->offset); *o_old = *o_begin; @@ -97,7 +109,7 @@ int lib_ring_buffer_try_reserve(const struct lib_ring_buffer_config *config, if (last_tsc_overflow(config, buf, ctx->tsc)) ctx->rflags |= RING_BUFFER_RFLAG_FULL_TSC; - if (unlikely(subbuf_offset(*o_begin, chan) == 0)) + if (caa_unlikely(subbuf_offset(*o_begin, chan) == 0)) return 1; ctx->slot_size = record_header_size(config, chan, *o_begin, @@ -105,7 +117,7 @@ int lib_ring_buffer_try_reserve(const struct lib_ring_buffer_config *config, ctx->slot_size += lib_ring_buffer_align(*o_begin + ctx->slot_size, ctx->largest_align) + ctx->data_size; - if (unlikely((subbuf_offset(*o_begin, chan) + ctx->slot_size) + if (caa_unlikely((subbuf_offset(*o_begin, chan) + ctx->slot_size) > chan->backend.subbuf_size)) return 1; @@ -115,7 +127,7 @@ int lib_ring_buffer_try_reserve(const struct lib_ring_buffer_config *config, */ *o_end = *o_begin + ctx->slot_size; - if (unlikely((subbuf_offset(*o_end, chan)) == 0)) + if (caa_unlikely((subbuf_offset(*o_end, chan)) == 0)) /* * The offset_end will fall at the very beginning of the next * subbuffer. @@ -142,11 +154,12 @@ int lib_ring_buffer_try_reserve(const struct lib_ring_buffer_config *config, */ static inline -int lib_ring_buffer_reserve(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer_ctx *ctx) +int lib_ring_buffer_reserve(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer_ctx *ctx) { struct channel *chan = ctx->chan; - struct lib_ring_buffer *buf; + struct lttng_ust_shm_handle *handle = ctx->handle; + struct lttng_ust_lib_ring_buffer *buf; unsigned long o_begin, o_end, o_old; size_t before_hdr_pad = 0; @@ -154,9 +167,9 @@ int lib_ring_buffer_reserve(const struct lib_ring_buffer_config *config, return -EAGAIN; if (config->alloc == RING_BUFFER_ALLOC_PER_CPU) - buf = &shmp(chan->backend.buf)[ctx->cpu]; + buf = shmp(handle, chan->backend.buf[ctx->cpu].shmp); else - buf = shmp(chan->backend.buf); + buf = shmp(handle, chan->backend.buf[0].shmp); if (uatomic_read(&buf->record_disabled)) return -EAGAIN; ctx->buf = buf; @@ -164,11 +177,11 @@ int lib_ring_buffer_reserve(const struct lib_ring_buffer_config *config, /* * Perform retryable operations. */ - if (unlikely(lib_ring_buffer_try_reserve(config, ctx, &o_begin, + if (caa_unlikely(lib_ring_buffer_try_reserve(config, ctx, &o_begin, &o_end, &o_old, &before_hdr_pad))) goto slow_path; - if (unlikely(v_cmpxchg(config, &ctx->buf->offset, o_old, o_end) + if (caa_unlikely(v_cmpxchg(config, &ctx->buf->offset, o_old, o_end) != o_old)) goto slow_path; @@ -189,7 +202,7 @@ int lib_ring_buffer_reserve(const struct lib_ring_buffer_config *config, * Clear noref flag for this subbuffer. */ lib_ring_buffer_clear_noref(config, &ctx->buf->backend, - subbuf_index(o_end - 1, chan)); + subbuf_index(o_end - 1, chan), handle); ctx->pre_offset = o_begin; ctx->buf_offset = o_begin + before_hdr_pad; @@ -213,10 +226,11 @@ slow_path: * disabled, for RING_BUFFER_SYNC_PER_CPU configuration. */ static inline -void lib_ring_buffer_switch(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf, enum switch_mode mode) +void lib_ring_buffer_switch(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf, enum switch_mode mode, + struct lttng_ust_shm_handle *handle) { - lib_ring_buffer_switch_slow(buf, mode); + lib_ring_buffer_switch_slow(buf, mode, handle); } /* See ring_buffer_frontend_api.h for lib_ring_buffer_reserve(). */ @@ -230,11 +244,12 @@ void lib_ring_buffer_switch(const struct lib_ring_buffer_config *config, * specified sub-buffer, and delivers it if necessary. */ static inline -void lib_ring_buffer_commit(const struct lib_ring_buffer_config *config, - const struct lib_ring_buffer_ctx *ctx) +void lib_ring_buffer_commit(const struct lttng_ust_lib_ring_buffer_config *config, + const struct lttng_ust_lib_ring_buffer_ctx *ctx) { struct channel *chan = ctx->chan; - struct lib_ring_buffer *buf = ctx->buf; + struct lttng_ust_shm_handle *handle = ctx->handle; + struct lttng_ust_lib_ring_buffer *buf = ctx->buf; unsigned long offset_end = ctx->buf_offset; unsigned long endidx = subbuf_index(offset_end - 1, chan); unsigned long commit_count; @@ -242,7 +257,7 @@ void lib_ring_buffer_commit(const struct lib_ring_buffer_config *config, /* * Must count record before incrementing the commit count. */ - subbuffer_count_record(config, &buf->backend, endidx); + subbuffer_count_record(config, &buf->backend, endidx, handle); /* * Order all writes to buffer before the commit count update that will @@ -250,7 +265,7 @@ void lib_ring_buffer_commit(const struct lib_ring_buffer_config *config, */ cmm_smp_wmb(); - v_add(config, ctx->slot_size, &shmp(buf->commit_hot)[endidx].cc); + v_add(config, ctx->slot_size, &shmp_index(handle, buf->commit_hot, endidx)->cc); /* * commit count read can race with concurrent OOO commit count updates. @@ -270,17 +285,17 @@ void lib_ring_buffer_commit(const struct lib_ring_buffer_config *config, * count reaches back the reserve offset for a specific sub-buffer, * which is completely independent of the order. */ - commit_count = v_read(config, &shmp(buf->commit_hot)[endidx].cc); + commit_count = v_read(config, &shmp_index(handle, buf->commit_hot, endidx)->cc); lib_ring_buffer_check_deliver(config, buf, chan, offset_end - 1, - commit_count, endidx); + commit_count, endidx, handle); /* * Update used size at each commit. It's needed only for extracting * ring_buffer buffers from vmcore, after crash. */ lib_ring_buffer_write_commit_counter(config, buf, chan, endidx, ctx->buf_offset, commit_count, - ctx->slot_size); + ctx->slot_size, handle); } /** @@ -294,10 +309,10 @@ void lib_ring_buffer_commit(const struct lib_ring_buffer_config *config, * Returns 0 upon success, -EPERM if the record cannot be discarded. */ static inline -int lib_ring_buffer_try_discard_reserve(const struct lib_ring_buffer_config *config, - const struct lib_ring_buffer_ctx *ctx) +int lib_ring_buffer_try_discard_reserve(const struct lttng_ust_lib_ring_buffer_config *config, + const struct lttng_ust_lib_ring_buffer_ctx *ctx) { - struct lib_ring_buffer *buf = ctx->buf; + struct lttng_ust_lib_ring_buffer *buf = ctx->buf; unsigned long end_offset = ctx->pre_offset + ctx->slot_size; /* @@ -314,7 +329,7 @@ int lib_ring_buffer_try_discard_reserve(const struct lib_ring_buffer_config *con */ save_last_tsc(config, buf, 0ULL); - if (likely(v_cmpxchg(config, &buf->offset, end_offset, ctx->pre_offset) + if (caa_likely(v_cmpxchg(config, &buf->offset, end_offset, ctx->pre_offset) != end_offset)) return -EPERM; else @@ -322,31 +337,31 @@ int lib_ring_buffer_try_discard_reserve(const struct lib_ring_buffer_config *con } static inline -void channel_record_disable(const struct lib_ring_buffer_config *config, +void channel_record_disable(const struct lttng_ust_lib_ring_buffer_config *config, struct channel *chan) { uatomic_inc(&chan->record_disabled); } static inline -void channel_record_enable(const struct lib_ring_buffer_config *config, +void channel_record_enable(const struct lttng_ust_lib_ring_buffer_config *config, struct channel *chan) { uatomic_dec(&chan->record_disabled); } static inline -void lib_ring_buffer_record_disable(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf) +void lib_ring_buffer_record_disable(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf) { uatomic_inc(&buf->record_disabled); } static inline -void lib_ring_buffer_record_enable(const struct lib_ring_buffer_config *config, - struct lib_ring_buffer *buf) +void lib_ring_buffer_record_enable(const struct lttng_ust_lib_ring_buffer_config *config, + struct lttng_ust_lib_ring_buffer *buf) { uatomic_dec(&buf->record_disabled); } -#endif /* _LINUX_RING_BUFFER_FRONTEND_API_H */ +#endif /* _LTTNG_RING_BUFFER_FRONTEND_API_H */